Minim stream being throttled on QNAP NAS ?

[windbag]

(30-11-2024 18:19)simoncn Wrote:  In standard UPnP, it works like this:...

Thanks or the great amount of detail, simoncn.
A whole load of questions come to mind, but I'll leave those to another post.
First I'll report other findings.

(30-11-2024 18:19)simoncn Wrote:  ...the device reading the audio data from MinimServer has the IP address 192.168.0.72. If this is the IP address of your Sonos renderer, there is no URL proxying. If this is the IP address of the phone running BubbleUPnP, this means that URL proxying is happening.

That is my phone => URL proxying is happening
What is governing this and what are the implications of that ?
Does this mean that Bubble on the phone IS doing transcoding?

My main music database, where I rip my CDs to directly, is currently 1.02 TB with over 100k files in it. I rip CDs to album-based folders with FLAC & Mp3 as the main output into my main music database. I've always ripped to flac for fidelity when needed, and VBR mp3 to get the best lossy quality while keeping size to a minimum. Embedded artwork is limited to 30kB per track.
Currently, the full database has over 24k flac files (719GB) & almost 32k mp3 flies (230GB).
A big aim is to use m3u files as my preferred selections by artist, the equivalent of how I used to make cassette tapes.
One aim was to have my music available in the car and/or on the phone, where quality is not paramount, but storage is at a premium - so a subset of that full database is needed.
I make a separate extract for that by copying just the mp3 and m3u files to an extract area - almost exclusively VBR mp3 files.
It is that smaller area that I had hooked to Minim as the contentDir. This worked well until about 6 weeks ago, when the stuttering suddenly started.

As recent efforts to try & cure this failed, in a last resort I threw the full music database as the contentDir.
Minim still scanned OK, and not surprisingly, Bubble took somewhat longer to give the folder view. Trying similar mp3 files to before, stuttering was a bad as ever.

A new option was to play the flac files.
The first set played perfectly.
So did the second.
So have a few others.

So, there is NO inference affecting the Sonos units.
Whatever is making the stream from the the VBR mp3s must be suspect in the stuttering. The Sonos have been playing these for years without issue & have not been updated, so they can't be the source of the issue.

One important note was the Bubble display in 'Now playing', which showed as WAV 44.1kHz - whereas the stuttering VBR files were FFMpeg-based.

Another thing I did was to specifically make a fixed-rate 192 kHz mp3 set of album tracks to see how they played.
Those, too stuttered.

I made a quick dive into the Bubble settings, and realised I left them in a state where they initially worked, but had little idea of what was optimal.

In particular, having to play to the lead SONOS in a group as the target meant that if the Sonos units had been grouped so that a different unit was 'the lead', then the ability of Bubble to have different settings for every Sonos target meant that Sonos regrouping could give a totally different performance.

Crucially, the Renderer setting for FFmpeg audio decoding was set as 'formats not natively supported' rather than Never Use or Always Use.
My recollection is that Sonos reports to Bubble that it can't use some of the normal formats, so perhaps that is why I'd left on the setting I found - and what it was actually doing is not clear.

Similarly, the max supported sample rate was 192 Khz. Whether this should be unlimited or 44.1Khz is not obvious.

So when I said I hadn't set up transcoding on Bubble, it looks like that was incorrect.

I guess I need to switch to the Bubble forum to try and work out what all those renderer settings ought to be, unless anyone here already knows.